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Jon Finch
04-05-2010, 12:55 AM
I had the opportunity to spend a few hours in the shop today and got a bunch of bowls roughed out. I split a poplar crotch and decided to give it a go (I've never turned a crotch before). The first side of the log turned out just fine:

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Notice the bark that is in the crotch. Is there anything I should or can do to make this bowl finish out ok? It's easily the largest thing I've ever turned (~15" diameter).

The mating side of the log didn't turn out so nice. I got a pretty good scare when the blank split in two while roughing out the outside :eek:. To be honest, I had no idea the bark ran continuous throughout. I need to pay more attention to my blanks...

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But as you can tell from the floor... I did have a good afternoon :D

Paul Atkins
04-05-2010, 1:11 AM
I've had my dog in my lap - is that close enough?

Jon Finch
04-05-2010, 1:19 AM
I think you and I would get a long just fine outside this forum, Paul :D.
(but I did have to read your post a couple times to figure out what the heck you were talking about...)

Mark Norman
04-05-2010, 1:28 AM
jon, that wood is sweet!! at least ya got one of the two and did not get hurt.

John Keeton
04-05-2010, 7:07 AM
Jon, I think you are darn lucky that this one didn't come apart on you!! It is certainly a very nice looking piece of wood, though. I would think putting some glue in the bark before finishing would help keep it from cracking badly in the future, and stabilize the bark.

Steve Schlumpf
04-05-2010, 8:51 AM
Jon - glad you were not hit by the flying chunk of wood! At least you learned what can happen with bark inclusions and will be on the look out for them in the future!

On your rough out bowl - lets say that the bowl survives the drying process and you decide to finish turn it. Check the bowl over really good and see if there are any cracks in the bark inclusion area before turning. You can CA the bark area but understand that as you finish turn the bowl - the small section of wood that is presently holding the blank together will be getting thinner and thinner and it's holding ability will shrink right along with it.

Be sure to use sharp tools, light cuts and keep your lathe speed down so that you do not introduce excessive centrifugal force to the blank.

Best of luck with this! Looking forward to seeing the finished piece but, above all - be safe!

Al Wasser
04-05-2010, 9:47 AM
Don't ya just hate it when you have to stop and sweep up! That's an awesome piece of wood.

Bernie Weishapl
04-05-2010, 10:09 AM
Ditto what Steve said. That is going to be a awesome bowl but be careful.

Jon Finch
04-05-2010, 11:49 AM
Yeah I think the finish turning on that bowl will be a lesson in trepidation. That is assuming it doesn't just split into two pieces while drying.

charlie knighton
04-05-2010, 11:57 AM
Jon, i am glad you are ok, if in the future you can turn the outside without it coming apart, when doing the inside, duct tape the outside

bark inclusions and sap inclusions even rock inclusions if turning root balls all are iffy, there really is no way to know, one thing is to make sure someone checks on you while you are turning those things :eek:

Bill Bolen
04-05-2010, 12:58 PM
You've gotten a lot of good advice. When I have a bark inclusion 1/2 half way through the bowl or more, once dry I scrape out any loose bark and fill the void with epoxy mixed with coffee grounds. Holds things together quite well and the large dark streak where the epoxy/coffee is adds a bit of interest...Bill...

Jon Finch
04-07-2010, 9:59 AM
Well I know better then to do anything other then burn this one:

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So, is there any way to predict which crotches are going to be turnable and which are going to be full of bark?

steven carter
04-07-2010, 10:54 AM
Jon,

While not a definitive answer, my experience has been that the more the crotch is shaped like V the more chance of bark, and when the crotch is more shaped like U then less chance of bark. Anyone else find this to be the case?

Steve

Steve Schlumpf
04-07-2010, 10:55 AM
Jon - you have good wood either side of the bark area and could turn something like a vase or a small HF.

I am not aware of any way to predict unsafe inclusions as each tree is unique. The key to all of this is to be aware of the problems associated with bark inclusions and be safe about it!